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Interference of the essential oil of Lippia alba (MILL.) NE Brown chemotype II Leaves on the oxacillin antimicrobial activity upon oxacillin-resistant Staphylococcus aureus / InterferÃncia do Ãleo essencial de folhas do Quimiotipo II de LIPPIA ALBA (MILL.) N.E. Brown na atividade antimicrobiana da oxacilina sobre Staphylacoccus aureus oxacilina-resistenteLarissa Queiroz Rocha 19 January 2012 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / The Lippia alba (Mill.) N. E. Brown species inhabits almost all regions of Brazil, which is plenty used in popular medicine. Studies show that between the Brazilian Northeast three chemotypes of L. alba, the chemotype II (OELaII), produces in its leaves, essential oil with the largest and broadest antimicrobial potential. The objective of this study was to evaluate the interference of the OELaII in the Oxacillin activity and its mechanism of action against Staphylococcus aureus. The antimicrobial activity was performed by determining the Minimum Inhibitory Concentration (MIC) and minimum bactericidal concentration (MBC) by broth microdilution methods of culture and spreading on the surface of agar Plate-Count, respectively. The evaluation of the OELaII interference on antimicrobial oxacillin activity and other antibiotics was performed by using methodology changed disk diffusion. The checkerboard method, calculation of Fractional Inhibitory Concentration Indices and graphing Isobologramas was used to assess the interference OELaII the antimicrobial activity oxacillin. The study of the OELaII mechanism of action on strains of S. aureus was performed by evaluating the OE antimicrobial activity in the phases of exponential growth and stationary as well as by the action of chloramphenicol on the exponential growth. The effect of OELaII, oxacillin and OELaII-OXA exposure time, on strains of S. aureus was observed by tracing curves time of death, was considered synergistic association was found that a reduction in the number of viable cells after 24-48 hours when compared to each compound alone. The results revealed that the MIC and MBC OELaII to the strains of S. aureus oxacillin resistant (ORSA) are equal or very close to those observed for susceptible strains (UR) ranging from 0.312 to 1.25 mg / ml and 1.25 to 5.0 mg / mL for the first, and 0.312 -0.625 mg / mL and 0.625 to 2.5 mg / mL for the second. Oxacillin to the values obtained were 6.25 to 200 mg / ml and 25 and 400 mg / mL and 0.390 to 3.12 for ORSA mg / mL and 0.781 to 6.25 mg / mL for the UR. The study of the evaluation of synergism using the Kirby-Bauer method and checkerboad showed that the interference exerted by the essential oil on the antimicrobial action vary with the type of antibiotic and the type of strain tested. Isobologram charts obtained by checkerboard method suggests a synergism between good and OELaII Oxacillin for all the microorganisms tested. The study of the mechanism of action on inhibition OELaII /death ORSA strains, it was found that the OELaII reduced the number of viable cells in any growth stage. The same was not observed when cell division was halted by the presence of chloramphenicol, suggesting that OE acts mainly in the exponential growth phase (intense cell division). The death curve by microbial activity and OELaII Oxacillin showed a synergistic effect for the association OELaII-OXA, with a logarithmic decrease significantly when compared to treatment done alone. Given this biological potential, this study suggests that the Lippia alba can be used as a pharmaceutical ingredient in preparations of association with antimicrobial drugs in order to diminish the toxicity and increase its spectrum. However, there is the importance of studies on the elucidation of the different molecular targets through knowledge of its mechanism of action and toxicity testing in vitro, thus providing the safety and therapeutic efficacy of this important plant species users. / A espÃcie Lippia alba (Mill.) N. E. Brown habita praticamente todas as regiÃes do Brasil, onde à muito empregada na medicina popular. Estudos mostram que, entre os trÃs quimiotipos de L. alba do Nordeste Brasileiro, o quimiotipo II (OELaII), produz, em suas folhas, o Ãleo essencial com o maior e mais amplo potencial antimicrobiano. O objetivo deste estudo foi avaliar a interferÃncia do OELaII na atividade de Oxacilina e o seu mecanismo de aÃÃo frente a cepas de Staphylococcus aureus. A avaliaÃÃo da atividade antimicrobiana foi realizada pela determinaÃÃo da ConcentraÃÃo InibitÃria MÃnima (CIM) e ConcentraÃÃo Bactericida MÃnima (CBM), pelos mÃtodos de microdiluiÃÃo em caldo de cultura e espalhamento na superfÃcie do Ãgar Plate-Count, respectivamente. A avaliaÃÃo da interferÃncia do OELaII na atividade antimicrobiana da Oxacilina e outros antibiÃticos de uso foi realizada pela metodologia de disco-difusÃo modificado. O mÃtodo de Checkerboard, cÃlculo dos Indices da ConcentraÃÃo InibitÃria Fracionada e construÃÃo de grÃficos Isobologramas foi utilizado na avaliaÃÃo da interferÃncia do OELaII na atividade antimicrobiana da Oxacilina. O estudo do mecanismo de aÃÃo do OELaII sobre cepas de S. aureus foi realizado pela avaliaÃÃo da atividade antimicrobiana do OE nas fases de crescimento exponencial e estacionÃrio, bem como pela aÃÃo do cloranfenicol sobre o crescimento exponencial. O efeito do tempo de exposiÃÃo ao OELaII, Oxacilina e OELaII-OXA sobre cepas de S. aureus foi verificado pelo traÃado das curvas de tempo de morte, sendo considerado sinergismo as associaÃÃes em que foi verificado uma reduÃÃo do nÃmero de cÃlulas viÃveis, apÃs 24-48 horas quando comparado a cada composto isoladamente. Os resultados obtidos revelaram que a CIM e CBM do OELaII para cepas de S. aureus oxacilina-resistente (ORSA) sÃo iguais ou muito prÃximas Ãquelas constatadas para as cepas sensÃveis (OSSA), variando de 0,312-1,25 mg/mL e 1,25-5,0 mg/mL para a primeira; e 0,312-0,625 mg/mL e 0,625-2,5 mg/mL para a segunda. Para a Oxacilina os valores encontrados foram de 6,25-200 mg/mL e 25 e 400 mg/mL para as ORSA e 0,390-3,12 mg/mL e 0,781-6,25 mg/mL para as OSSA. O estudo da avaliaÃÃo do sinergismo, pelo mÃtodo de Kirby-Bauer e por checkerboad, mostrou que a interferÃncia exercida pelo Ãleo essencial sobre a aÃÃo dos antimicrobianos varia de acordo com o tipo de antibiÃtico e o tipo de cepa testada. Os grÃficos de isobolograma obtidos pelo mÃtodo de checkerboard sugerem um bom sinergismo entre o OELaII e a Oxacilina para todos os micro-organismos testados. Pelo estudo do mecanismo de aÃÃo do OELaII na inibiÃÃo/morte de cepas ORSA, verificou-se que o OELaII reduziu o nÃmero de cÃlulas viÃveis em qualquer estÃgio de crescimento. O mesmo nÃo foi verificado quando a divisÃo celular foi interrompida pela presenÃa de cloranfenicol, sugerindo que o OE age, principalmente, na fase exponencial de crescimento (intensa divisÃo celular). A curva de morte microbiana pela atividade do OELaII e Oxacilina, mostrou um efeito sinÃrgico para a associaÃÃo OELaII-OXA, com uma reduÃÃo logarÃtima significativa, quando comparado ao tratamento feito isoladamente. Diante desse importante potencial biolÃgico, este estudo sugere que a Lippia alba possa ser utilizado como insumo farmacÃutico em preparaÃÃes de associaÃÃo com medicamentos antimicrobianos visando a diminuir a toxicidade e aumentar o seu espectro de aÃÃo. Todavia, surge a importÃncia de estudos sobre a elucidaÃÃo dos diferentes alvos moleculares atravÃs do conhecimento do seu mecanismo de aÃÃo, bem como testes de toxicidade in vitro, oferecendo assim, seguranÃa e eficÃcia terapÃutica aos usuÃrios dessa importantes espÃcie vegetal
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Conceptualisation et mise en oeuvre du processus Own Risk and Solvency Assessment pour l’assurance vie / Conceptualization and implementation of the Own Risk and Solvency Assessment process for life insuranceVedani, Julien 20 September 2016 (has links)
La directive Solvabilité II, soumise par la Commission Européenne en 2009, est rentrée en application en janvier 2016. Elle se base sur trois piliers. Le premier pilier traite des obligations quantitatives liées au calcul du capital de solvabilité requis. Le second pilier traite de la gouvernance des risques. Le troisième pilier concerne les documents et informations requis, la discipline de marché. Pour l’assurance vie, les obligations quantitatives (pilier I et une partie du pilier II) introduisent un haut niveau de complexité. En effet, pour créer un dispositif adapté aux spécificités des entreprises, la directive a introduit un cadre de valorisation du bilan des assureurs très délicat à comprendre et utiliser, la valorisation économique. Du fait de cette complexité, la plupart des assureurs vie européens ont, durant leurs premières années passées à implémenter la directive, choisi de se focaliser sur le pilier I en sachant que le calcul de l’exigence en capital serait une part essentielle du dispositif. Dans cette thèse, j’ai choisi de concentrer mon travail sur le second pilier de la directive et plus précisément sur le processus Own Risk and Solvency Assessment (ORSA). Cet outil réglementaire est en fait la seconde source de complexité majeure de Solvabilité II. C’est un processus de gestion des risques totalement intégré à l’entreprise dont l’objectif est de mener les assureurs à une meilleure compréhension de leurs risques. Au cours de mon travail, j’ai cherché à conceptualiser et à proposer des mises en œuvre opérationnelles pour répondre aux problématiques induites par l’ORSA (calcul du Besoin Global de Solvabilité et Conformité Permanente). Enfin, au travers d’un travail commun avec N. El Karoui, S. Loisel et J.-L. Prigent, nous avons analysé et exemplifié certains des dangers majeurs induits par la valorisation économique / The Solvency II directive issued in 2009 by the European Commission has been put into action in January 2016. It is based on three pillars. The first pillar addresses the quantitative requirements to assess the Solvency capital needs. The second pillar, more qualitative, addresses the risks governance. The third pillar addresses the required disclosures. For life insurance, the quantitative requirements (pillar I and a part of pillar II) have introduced a high level of complexity. Indeed, to create an entity-adapted scheme, the directive has developed a very specific process to evaluate the insurance balance sheets, namely the economic valuation. Considering this complexity, most European life insurances have chosen to focus on pillar I, at the beginning of the implementation of the directive, the regulatory capital assessment being an essential part of the solvency scheme. In this thesis I focus my work on the second pillar of the directive and more precisely on the Own Risk and Solvency Assessment (ORSA) process. This regulatory tool is the second major source of complexity when implementing the directive. It is a completely undertaking-embedded risk management process which aims to deepen the insurance knowledge of its risks. In my work I have tried to conceptualize and propose operational implementations to answer the ORSA issues (Overall Solvency Needs assessment and continuous compliance). Finally, through a joint work with N. El Karoui, S. Loisel and J.-L. Prigent, we have underlined, analyzed and exemplified some of the major hazard sources induced by the economic valuation
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Vindkraft i Dalarna : Från acceptans och lokalisering till planering och eftertankeGradén, Mattias January 2011 (has links)
This thesis examines prerequisites for wind power diffusion in a county in Sweden that quite recently was concidered to be of interest for electricty production from renewable energy sources. Three different municipalities: Falun, Mora and Orsa in the county of Dalarna are highlighted. Their view on permitting processes of wind power installations are investigated. Other actors, such as exploiters and local citizens are also being analysed. This study shows that the local acceptance was very high when the first wind power parks were built, much thanks to local politicians and local citizens. For the politicians the wind power symbolised a key to a better green society, for the local citizens the wind power meant some economical advantages. The first wind power parks were localised to areas because of good wind conditions and social factors, especially from local communities. However, results from this study shows that the acceptance for wind power the last few years, in generel, has decreased. The local authorities have also been conscious of some negative consequenses from already built wind power parks. As a response they started to add planning tools to the permitting process.
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Kriskommunikation när konsekvenserna av djurparker drabbar människan : En fallstudie av de tragiska olyckorna som drabbade Kolmården Djurpark och Orsa RovdjursparkOlin, Sanna January 2018 (has links)
2012 respektive 2017 mister två djurskötare sina liv på två olika djurparker i Sverige, den ena efter ett rutinmässigt arbete inne hos vargarna på Kolmården och den andra i inhägnaden för björnar på Orsa Rovdjurspark. De båda djurparkerna står mitt i offentlighetens insyn och kan inte ge information om hur detta kunde ske, något som väcker känslor bland allmänheten. Denna uppsats kommer att studera de två händelser som skett på Kolmården Djurpark och Orsa Rovdjurspark där två anställda miste sina liv i samband med rutinmässiga besök inne hos vargarna på Kolmården Djurpark respektive björnarna på Orsa Rovdjurspark. Studien går ut på att undersöka de båda djurparkernas kriskommunikation efter händelserna med hjälp av pressmeddelanden från respektive organisation samt artiklar i nyhetsmedier. Vad skiljer kommunikationen åt mellan dessa djurparker och vad förmedlar medier? Genom kritisk diskursanalys har pressmeddelanden samt artiklar granskas i syfte att studera kommunikationen kring händelserna, där bland annat Faircloughs tredimensionella kritiska diskursanalys tas upp för att grunda den data som samlats in och senare även resultatet. Uppsatsen har, som tidigare nämnt, fokuserat på pressmeddelanden och nyhetsartiklar men ett antal intervjuer har även blivit genomförda för att ge en bild av de vilda djuren jämfört med de instängda djuren. Dessa intervjuer har genomförts med forskare och organisationer som specialiserar sig på studier av vilda björnar och vargar. Både Kolmårdens djurpark och Orsa Rovdjurspark kontaktades för att delta i intervjuer men de båda djurparkerna valde att avstå från deltagande i denna studie.
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Aspectos epidemiológicos, fisiológicos e moleculares da resistência à oxacilina em Staphylococcus aureus e avaliação da sua susceptibilidade a novas moléculas sintéticasNascimento, Thiago César 24 April 2014 (has links)
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Previous issue date: 2014-04-24 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Staphylococcus aureus é uma das principais causas de infecções associadas à saúde em todo o mundo. O objetivo deste trabalho foi avaliar as características epidemiológicas, fisiológicas e moleculares de S. aureus resistente à oxacilina (ORSA), isolados de infecções em um hospital terciário universitário e avaliar sua susceptibilidade a novas moléculas síntéticas. Foram avaliadas um total de 103 amostras de ORSA quanto a dados clínicos e epidemiológicos relacionados aos pacientes, perfil de susceptibilidade a drogas antimicrobianas, avaliação da produção de biofilme e da capacidade hemolítica e confirmação da identidade genética, detecção do gene mecA e caracterização do SCCmec, por PCR. Para 45 amostras oriundas do CTI, também foram realizadas a análise do perfil de fragmentação do DNA cromossômico por PFGE e caracterização do CC, por PCR. Para 21 amostras foi avaliada a susceptibilidade a aminas aromáticas alquiladas (aminoálcoois). Considerando-se as amostras clínicas, a maioria das amostras foi isolada no sexo masculino (71%) a partir de secreção traqueal (26,2%) e sangue (23,3%) seguido de swab de sítio cirúrgico e ponta do cateter (15,5%), exsudados (14,6%) e urina (4,9%), associados à infecção do sistema respiratório (34%) e bacteremia (20,4%), em unidade de terapia intensiva (43,7%). No geral, uma alta frequência de resistência foi observada contra clindamicina (100%), eritromicina (100%), azitromicina (99%), levofloxacina (93,2%), gentamicina (84,5%), sulfametoxazol-trimetoprim (75,7%), tetraciclina (77,6%), cloranfenicol (59,3%) e rifampicina (50,5%). Os aminoálcoois também apresentaram atividade antibacteriana contra a maioria dos isolados de ORSA. Tipos de SCCmec III (66,7%) , II (17,8%) , IV (4,4% ), I (2,2%) foram encontrados. A maioria (66,7%) dos isolados foram relacionados ao clone epidemico brasileiro (CEB)/CC8/SCCmec III , que prevaleceu entre 2005 e 2008 , enquanto que a linhagem USA100/CC5/SCCmec II surgiu em 2007 e foi mais frequente em 2009 e 2010, na UTI. Os isolados que transportam o tipo de SCCmec IV (USA400/CC1 e USA800/CC5 linhagens) e I (USA500/CC5) também foram detectadas. Nossos dados são altamente relevantes para os sistemas de vigilância permitiu mapear em maior escala a circulação dinâmica de ORSA e levantar discussões sobre estratégias de contenção e uso racional da quimioterapia empírica. / Staphylococcus aureus is a major cause of health care associated infections worldwide. The aim of this work was to evaluate epidemiological, physiological and molecular characteristics of aureus oxacillin resistant S. aureus (ORSA) isolated from infections in a tertiary university hospital and evaluated their susceptibility to new synthetic molecules. A total of 103 samples of ORSA for clinical and epidemiological data related to patients susceptibility profile to antimicrobial drugs, assessment of biofilm production and hemolytic capacity and confirmation of genetic identity, detection of the mecA gene and characterization of SCCmec were evaluated, PCR. For 45 samples from CTI, also the profile of DNA analysis by PFGE and characterization of the CC, PCR were performed. For 21 samples susceptibility to alkylated aromatic amines was evaluated. Considering the clinical samples, most samples contained in males (71%) from tracheal secretion (26.2%) and blood (23.3%) followed by surgical site and swab tip of the catheter (15.5%), exudates (14.6 %) and urine (4.9%), associated with infection of the respiratory system (34%) and bacteremia (20.4%) in the intensive care unit (43.7%). Overall, a high frequency of resistance was observed against clindamycin and erythromycin (100%), azithromycin (99%), levofloxacin (93.2%), gentamicin (84.5%), trimethoprim-sulfamethoxazole (75.7%), tetracycline (77.6%), chloramphenicol (59.3%) and rifampicin (50.5%). The amino alcohols also showed antibacterial activity against most isolates of ORSA. SCCmec type III (66.7%), II (17.8%), IV (4.4%) and I (2.2%) were found. The majority (66.7%) isolates were related to the brazilian epidemic clone (CEB)/CC8/SCCmec III, which prevailed between 2005 and 2008, while the USA100/CC5/SCCmec lineage II emerged in 2007 and was more frequent in 2009 and 2010 in the ICU. The strains carrying the SCCmec type IV (USA400/CC1 and USA800/CC5 lineages) and I (USA500/CC5) were also detected. Our data are highly relevant to surveillance systems enabled map on a larger scale the dynamic movement of ORSA and raise discussions on containment strategies and rational use of empirical chemotherapy.
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Measuring and managing operational risk in the insurance and banking sectors / Mesure et gestion du risque opérationnel en assurance et financeKaram, Elias 26 June 2014 (has links)
Notre intérêt dans cette thèse est de combiner les différentes techniques de mesure du risque opérationnel dans les secteurs financiers, et on s'intéresse plus particulièrement aux conséquences du risque d'estimation dans les modèles, qui est un risque opérationnel particulier. Nous allons présenter les concepts mathématiques et actuariels associés ainsi qu'une application numérique en ce qui concerne l'approche de mesure avancée comme Loss Distribution pour calculer l'exigence en capital. En plus, on se concentre sur le risque d'estimation illustré avec l'analyse des scénarios de l'opinion d'experts en conjonction avec des données de pertes internes pour évaluer notre exposition aux évènements de gravité. Nous concluons cette première partie en définissant une technique de mise l'échelle sur la base de (MCO) qui nous permet de normaliser nos données externes à une banque locale Libanaise.Dans la deuxième partie, on donne de l'importance sur la mesure de l'erreur induite sur le SCR par l'erreur d'estimation des paramètres, on propose une méthode alternative pour estimer une courbe de taux et on termine par attirer l'attention sur les réflexions autour des hypothèses de calcul et ce que l'on convient de qualifier d'hypothèse "cohérente avec les valeurs de marché" serait bien plus pertinente et efficace que la complexification du modèle, source d'instabilité supplémentaire, ainsi mettre en évidence le risque d'estimation qui est lié au risque opérationnel et doit être accordé beaucoup plus d'attention dans nos modèles de travail / Our interest in this thesis is first to combine the different measurement techniques for operational risk in financial companies, and we highlight more and more the consequences of estimation risk which is treated as a particular part of operational risk. In the first part, we will present a full overview of operational risk, from the regulatory laws and regulations to the associated mathematical and actuarial concepts as well as a numerical application regarding the Advanced Measurement Approach, like Loss Distribution to calculate the capital requirement, then applying the Extreme Value Theory. We conclude this first part by setting a scaling technique based on (OLS) enabling us to normalize our external data to a local Lebanese Bank. On the second part, we feature estimation risk by first measuring the error induced on the SCR by the estimation error of the parameters, to having an alternative yield curve estimation and finishing by calling attention to the reflections on assumptions of the calculation instead of focusing on the so called hypothesis "consistent with market values", would be more appropriate and effective than to complicate models and generate additional errors and instability. Chapters in this part illustrate the estimation risk in its different aspects which is a part of operational risk, highlighting as so the attention that should be given in treating our models
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Vindkraft i Dalarna : Från acceptans och lokalisering till planering och eftertankeGradén, Mattias January 2011 (has links)
This thesis examines prerequisites for wind power diffusion in a county in Sweden that quite recently was concidered to be of interest for electricty production from renewable energy sources. Three different municipalities: Falun, Mora and Orsa in the county of Dalarna are highlighted. Their view on permitting processes of wind power installations are investigated. Other actors, such as exploiters and local citizens are also being analysed. This study shows that the local acceptance was very high when the first wind power parks were built, much thanks to local politicians and local citizens. For the politicians the wind power symbolised a key to a better green society, for the local citizens the wind power meant some economical advantages. The first wind power parks were localised to areas because of good wind conditions and social factors, especially from local communities. However, results from this study shows that the acceptance for wind power the last few years, in generel, has decreased. The local authorities have also been conscious of some negative consequenses from already built wind power parks. As a response they started to add planning tools to the permitting process.
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Between the east and west : The pioneer settlement of Dalarna – Studies of lithic technology and raw material use at the Middle Mesolithic site Orsa 527Söderlind, Sandra January 2016 (has links)
In this thesis the pioneer settlement of northern Dalarna is investigated by means of a local study of lithic technology and raw material use on the Orsa 527 site in the area. This newly excavated site will be presented, for the first time in completion, in this thesis. The technological traits and raw material distribution on the site, which directly relate to the prehistoric people moving in this area during the Middle Mesolithic, are subsequently put into a larger regional perspective by comparing these results with other Middle Mesolithic sites in northern Dalarna and eastern Norway. Through the theoretical framework of chaîne opératoire and methods, such as dynamical classification of blades, the study of knapping properties of local raw materials and the study of raw material composition on five other sites in the area, questions regarding cultural transition, mobility and contacts can be discussed. The results of this work indicate that both technological and raw material parallels exist between eastern Norway and northern Dalarna during the Middle Mesolithic. This places these areas in a larger cultural sphere that was based on contacts and mobility during the pioneer settlement of the area.
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Provisionnement en assurance non-vie pour des contrats à maturité longue et à prime unique : application à la réforme Solvabilité 2 / Provisioning in non life insurance for contracts with long maturities and unique premium : Application to Solvency 2 reformNichil, Geoffrey 19 December 2014 (has links)
Nous considérons le cas d’un assureur qui doit indemniser une banque à la suite de pertes liées à un défaut de remboursement de ses emprunteurs. Les modèles couramment utilisés sont collectifs et ne permettent pas de prendre en compte les comportements individuels des emprunteurs. Dans une première partie nous définissons un modèle pour étudier le montant des pertes liées à ces défauts de paiement (provision) pour une période donnée. La quantité clé de notre modèle est le montant d’un défaut. Pour un emprunteur j et une date de fin de prêt Tj , ce montant vaut max(Sj Tj -Rj Tj ; 0), où Sj Tj est le montant dû par l’emprunteur et dépend de la durée et du montant du prêt, et Rj Tj est le montant de la revente du bien immobilier financé par le prêt. Rj Tj est proportionnel au montant emprunté; le coefficient de proportionnalité est modélisé par un mouvement Brownien géométrique et représente les fluctuations des prix de l’immobilier. La loi des couples (Date de fin du prêt, Durée du prêt) est modélisée par un processus ponctuel de Poisson. La provision Ph, où h est la durée maximale des contrats considérés, est alors définie comme la somme d’un nombre aléatoire de montants de défauts individuels. Nous pouvons ainsi calculer l’espérance et la variance de la provision mais aussi donner un algorithme de simulation. Il est également possible d’estimer les paramètres liés au modèle et de fournir une valeur numérique aux quantiles de la provision. Dans une deuxième partie nous nous intéresserons au besoin de solvabilité associé au risque de provisionnement (problématique imposée par la réforme européenne Solvabilité 2). La question se ramène à étudier le comportement asymptotique de Ph lorsque h ! +1. Nous montrons que Ph, convenablement normalisée, converge en loi vers une variable aléatoire qui est la somme de deux variables dont l’une est gaussienne / We consider an insurance company which has to indemnify a bank against losses related to a borrower defaulting on payments. Models normally used by insurers are collectives and do not allows to take into account the personal characteristics of borrowers. In a first part, we defined a model to evaluate potential future default amounts (provision) over a fixed period.The amount of default is the key to our model. For a borrower j and an associated maturity Tj, this amount is max(Sj Tj -Rj Tj ; 0), where Sj Tj is the outstanding amount owed by the borrower and depends on the borrowed amount and the term of the loan, and Rj Tj is the property sale amount. Rj Tj is proportionate to the borrowed amount; the proportionality coefficient is modeled by a geometric Brownian motion and represents the fluctuation price of real estate. The couples (Maturity of the loan, Term of the loan) are modeled by a Poisson point process. The provision Ph, where h is the maximum duration of the loans, is defined as the sum of the random number of individual defaults amounts. We can calculate the mean and the variance of the provision and also give an algorithm to simulate the provision. It is also possible to estimate the parameters of our model and then give a numerical value of the provision quantile. In the second part we will focus on the solvency need due to provisioning risk (topic imposed by the european Solvency 2 reform). The question will be to study the asymptotic behaviour of Ph when h ! +1. We will show that Ph, well renormalized, converges in law to a random variable which is the sum of two random variables whose one is a Gaussian
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Dealing with the ORSA : A Dynamic Risk-Factor Based Approach for the Small, Swedish Non-Life Insurer / Att handskas med ORSAn : En dynamisk riskfaktor-baserad metod för små, svenska skadeförsäkringsbolagSahlin, Carl, Hugner, Carl-Johan January 2013 (has links)
The Own Risk and Solvency Assessment, ORSA, is referred to as the heart of the regulation to be for European insurance companies - Solvency II. The aim of the ORSA process is to provide an overall and holistic view of the insurer’s risks by analyzing their current financial status and business strategy at hand. There is no predefined way to implement this process, which means that the companies are forced to develop a model themselves, as they see fit. In collaboration with a regional insurance company in Sweden we develop a structure and framework for an ORSA-model, flexible enough to be used by similar insurers yet standardized enough to overcome the issue of constrained resources within these smaller organizations. We apply a risk-factor based approach and tie together a balance sheet projection and stress testing, designed to be further developed as the individual insurer see fit. The suggested approach yields partially satisfying results and we consider the model to be particularly well-suited for assessing risk in the context of the small, non-life insurer. / Den egna risk- och solvensutvärderingen, ORSA, kallas hjärtat av det kommande regelverket för europeiska försäkringsbolag - Solvens II. Syftet med ORSA-processen är att ge en övergripande helhetsbild av försäkringsgivarens risker genom att analysera deras finansiella ställning och affärsstrategi. Det finns inget fördefinierat sätt att genomföra denna process, vilket innebär att företagen tvingas att utveckla en modell på egen hand, på ett sätt som de finner lämpligt. I samarbete med ett regionalt försäkringsbolag i Sverige utvecklar vi en struktur och en grund för en ORSA-modell. En modell som är tillräckligt flexibel för att kunna användas av liknande försäkringsgivare men samtidigt standardiserad nog att lösa problemet med begränsade resurser i dessa mindre organisationer. Vi tillämpar en riskfaktor-baserad metod, prognostiserar resultat- och balansräkning för bolaget och utför stresstester. Metoden är utformad för att utvecklas vidare av den enskilde försäkringsgivaren så som de finner lämpligt. Den föreslagna metoden ger delvis tillfredsställande resultat och vi anser att det är en grund väl lämpad att använda som utgångspunkt för att konstruera riskmätningsmetoder för små, skadeförsäkringsbolag.
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